Lock mechanism of large umbrella for effecting a section-less length adjustment of telescopic shank

ABSTRACT

A lock mechanism mounted in a large umbrella includes a sliding sleeve connected to spreaders and including a lower extension and an aperture on a surface of the extension, a telescopic shank, a lock device disposed in the shank, an actuation assembly including a hollow upper enlargement with the extension received therein, a transverse opening formed on the enlargement, and a spring biased actuation member adapted to have a portion disposed in the aperture for locking the extension in a closed position of the umbrella, the actuation member including a trigger, and a spring biased rib fixing assembly disposed between the handle and the actuation assembly. Pushing the trigger will disengage the portion with the aperture to unlock the extension for opening the umbrella. Also, turning the lock device will effect a subsequent section-less length adjustment of the shank.

BACKGROUND OF THE INVENTION

1. Field of Invention

The present invention relates to lock mechanisms of umbrella and more particularly to such a lock mechanism mounted in a large umbrella (e.g., beach umbrella, golf umbrella, or the like) capable of quickly effecting a section-less length adjustment of a telescopic shank in response to strong wind.

2. Description of Related Art

A conventional large umbrella (e.g., beach umbrella, golf umbrella, or the like) 1 is shown in FIGS. 1 and 2. The umbrella 1 comprises a shank 11, a plurality of spreaders 12, a lower sliding sleeve 13, an elongate actuation member 14, a handle 15, and a hub (not shown) at a top of the shank 11. A plurality of link bars are interconnected the spreaders 12 and the sleeve 13. The actuation member 14 comprises an upper flexible element 16 having a curved portion urged against an inner wall of the shank 11, a lower tab 17 disposed in a lower aperture 19 of the sleeve 13 in a locked state of the umbrella, and a bottom push button 18 adapted to push to cause the tab 17 to clear the aperture 19 for unlocking the umbrella. That is, a simple pressing of the push button 18 can automatically open the umbrella.

However, the flexible element 16 may suffer fatigue after a predetermined period time of use. And in turn, it may compromise the desired lock mechanism of the umbrella. Still however, the shank 11 is an elongate member and is not telescopic. Thus, a person, particularly a short person, may encounter great difficulties of operating the umbrella by holding the shank 11 when wind is heavy. Yet however, a telescopic shank 11 still cannot solve the problem since the engagement of a tab 17 and an aperture 19 of a sleeve 13 is relatively weak for a large umbrella (i.e., not reliable in use). A large curved member projected from an outer surface of a shank may solve the problem. However, its bulky size may adversely affect a normal operation of the umbrella.

U.S. Pat. No. 6,684,893 discloses a simplified controlling apparatus of an automatic umbrella. The '893 patent describes a spring-biased control loop and a projecting button. A first pressing of the button is adapted to move the control loop inward for opening the umbrella. A further pressing of the button will push a bullet-head to disengage with a shaft, thereby enabling a closing of the umbrella. However, the '893 patent is typically relatively complex in constructions, costly to manufacture, trouble-prone, unreliable in use, and cannot be mass produced easily.

Moreover, ribs cannot dispose in parallel relationship with the shank in a closed state of typical umbrella due to structure factor. Thus, rib tips may entangle with other objects when the umbrella and the objects are placed together. Thus, continuing improvements in the exploitation of a lock mechanism of large umbrella are constantly being sought.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a lock mechanism mounted in a large umbrella having a handle, a plurality of ribs, a plurality of spreaders, and a canopy, the lock mechanism comprising a sliding sleeve connected to the spreaders and including a lower extension and an aperture on a surface of the extension; a shank assembly including a telescopic shank and a lock device disposed in the shank; an actuation assembly including a hollow upper enlargement with the extension received therein, a transverse first opening formed on the enlargement, and a spring biased actuation member adapted to have a first predetermined portion disposed in the aperture for locking the extension in a closed position of the umbrella, and a second predetermined portion disposed externally of the enlargement; and a spring biased rib fixing assembly disposed between the handle and the actuation assembly, the rib fixing assembly being adapted to fix tips of the ribs in the closed position of the umbrella; whereby pushing the second predetermined portion of the actuation assembly will disengage the first predetermined portion with the aperture to unlock the extension of the sliding sleeve for sliding the sleeve upward to open the umbrella, and turning the lock device of the shank assembly will effect a subsequent section-less length or section-more length adjustment of the shank. By utilizing the present invention, it is possible of quickly effecting a section-less length adjustment of the shank in response to strong wind.

In a first aspect of the present invention, the shank comprises a fixed lower tube, a sliding upper tube adapted to partially slide into the lower tube, a coupling disposed on an upper end of the lower tube for preventing the lower tube from disengaging with the upper tube in which the coupling has an outer diameter smaller than an inner diameter of the sleeve such that the sleeve is adapted to pass through the coupling by sliding in opening or closing the umbrella, and a lock device secured to a lower end of the upper tube.

In a second aspect of the present invention, the lock device comprises a barbell member secured to the lower end of the upper tube and including an eccentric groove formed on an intermediate portion, an eccentric bar formed adjacent the groove, and a projecting stop formed on a surface of the bar; and a flexible, eccentric C-shaped fastening member fitted on the groove.

In a third another aspect of the present invention, the fastening member comprises an eccentric arcuate first member, an eccentric arcuate second member thinner than the first member, and a flexible portion interconnected the first and the second members, and a protuberance formed on a top of the second member.

In a fourth aspect of the present invention, the enlargement further comprises a receptacle opposite the first opening for anchoring the actuation member, and a lower projecting portion including a plurality of flanges formed therearound; the second predetermined portion of the actuation member is formed as a trigger; and the actuation member further comprises a loop interconnected the first and the second predetermined portions, a cavity formed in the first predetermined portion opposite the receptacle, and a first elastic member having one end anchored in the receptacle and the other end anchored in the cavity.

In a fifth aspect of the present invention, the rib fixing assembly comprises a cup including a bottom second opening urged against one of the flanges, and a second elastic member compressed between the cup and the handle in which the tips of the ribs are adapted to dispose proximate the cup in response to closing the umbrella.

The above and other objects, features and advantages of the present invention will become apparent from the following detailed description taken with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a portion of large umbrella incorporating a conventional lock mechanism in its locked state;

FIG. 2 is a view similar to FIG. 1 where the umbrella is open after pushing a push button;

FIG. 3 is a perspective view of a preferred embodiment of lock mechanism mounted in a large umbrella according to the invention;

FIG. 4 is an exploded perspective view of FIG. 3;

FIG. 5 is a transverse sectional view of lock device in its unlocked position;

FIG. 5A is a longitudinal sectional view of the lock device and the shank assembly in an unlocked position;

FIG. 6 is a transverse sectional view of the lock device in its locked position;

FIG. 6A is a longitudinal sectional view of the lock device and the shank assembly in a locked position;

FIG. 7 is a longitudinal sectional view of FIG. 3 where the umbrella is closed;

FIG. 7A is a detailed view of the area in a circle in FIG. 7;

FIG. 8 is a view similar to FIG. 7 where the umbrella is being opened;

FIG. 8A is a detailed view of the area in a circle in FIG. 8;

FIG. 9 is a view similar to FIG. 8 for showing a relative relationship of the sleeve and the lock device;

FIG. 10 is a view similar to FIG. 3 where the umbrella is fully open;

FIG. 11 is a view similar to FIG. 10 where rib tips are fixed by a rib fixing assembly;

FIG. 12 is an enlarged view of the rib fixing assembly and adjacent components where rib tips are disengaging with the rib fixing assembly by pressing the cup;

FIG. 13 is a perspective view of an umbrella incorporating the preferred embodiment of lock mechanism where canopy is tied and the rib tips are fixed by the rib fixing assembly in a closed position of the umbrella;

FIG. 14 is a perspective view of a prior umbrella in an open position for illustrating a distance between a virtual wind exertion plane on the canopy and the handle; and

FIG. 15 is a perspective view of an umbrella of the invention in an open position for illustrating a distance between a virtual wind exertion plane on the canopy and the handle.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 3 to 7A, a lock mechanism in accordance with a preferred embodiment of the invention mounted in a large umbrella is shown. The lock mechanism comprises a frame assembly 2, a shank assembly 3, an actuation assembly 4, and a rib fixing assembly 5. Each component is discussed in detailed below.

The frame assembly 2 comprises a handle 21, a sliding sleeve 22, a plurality of ribs 23, and a canopy 24 (see FIGS. 12 to 14). The sleeve 22 is provided with a top ring 25 with a plurality of cavities formed therearound for receiving the ribs 23 in a closed position of the umbrella, a lower extension 26, an aperture 27 on a surface of the extension 26, and two opposite projecting members 28 above the aperture 27 on the extension 26.

The shank assembly 3 comprises a shank 31, a coupling 32, and a lock device 33. The telescopic shank 31 comprises a fixed lower tube 311 and a sliding upper tube 312 adapted to partially slide into the lower tube 311 and joined the lower tube 311 at the coupling 32. Further, the lower tube 311 and the upper tube 312 are prevented from disengaging each other by the coupling 32. The coupling 32 has an outer diameter smaller than an inner diameter of the sleeve 22 such that the sleeve 22 is adapted to pass through the coupling 32 by sliding in opening or closing operation of the umbrella. Most portions of the coupling 32 are in sleeving relationship with an upper part of the lower tube 311. The coupling 32 comprises a top narrow section 321 having an inner diameter smaller than that of the lower tube 311 so as to cooperate with other lock arrangements as detailed later for preventing the lower tube 311 and the upper tube 312 from disengaging each other. The lock device 33 comprises an annular raised member 331 having an outer diameter smaller than an inner diameter of the upper tube 312 so as to dispose therein, a top protrusion 330 having a plurality of recesses 3301 formed therearound, the recesses 3301 being adapted to matingly engage with a plurality of projections 313 (as shown in FIG. 5A) formed around an inner surface of a lower portion of the upper tube 312 for fastening the protrusion 330 (i.e., the lock device 33) and the upper tube 312 together, an eccentric groove 332 formed below the raised member 331, an eccentric bar 333 formed adjacent the groove 332, a projecting stop 334 on a surface of the eccentric bar 333, a flexible C-shaped fastening member 335 fitted on the groove 332 to enclose the eccentric bar 333, the fastening member 335 having an outer diameter slightly smaller than an outer diameter of the raised member 331, the eccentric fastening member 335 including a thick first eccentric arcuate member 336, a thin second eccentric arcuate member 337, a flexible portion 338 interconnected the first and the second eccentric arcuate members 336 and 337, and a protuberance 339 formed on a top of the second eccentric arcuate member 337.

As shown in FIGS. 6 and 6A, a length adjustment of the shank assembly 3 is described below. The upper tube 312 turns about 180 degrees as indicated by arrow in FIG. 6. And in turn, the stop 334 urges against the protuberance 339 by temporarily deforming the flexible portion 338. Thus, both the bar 333 and the stop 334 urge the fastening member 335 against the inner surface of the lower tube 311. As such, the upper tube 312 is secured in the lower tube 311. This can effect a section-less length adjustment of the shank 31.

The actuation assembly 4 comprises a hollow cylinder 41, an actuation member 42, and a spring 43. The cylinder 41 is provided at a lower end of the shank assembly 3 and is projected from the handle 21. The cylinder 41 comprises an upper enlargement 411 including two opposite notches 413 on an inner surface engaged with the projecting member 28, a transverse opening 414, and a receptacle 415 (see FIG. 7A) opposite the opening 414; and a lower portion 412 including a plurality of annular flanges 416 provided in parallel on the outer surface of the lower portion 412. The actuation member 42 comprises a trigger 421 and a loop 422.

In assembly, insert the actuation member 42 into the enlargement 411 through the opening 414 with the spring 43 being compressed between the receptacle 415 and a recess of the loop 422 opposite the trigger 421 and the trigger 421 being disposed externally of the enlargement 411. Next, insert the lower extension 26 into the enlargement 411 until being stopped by an internal shoulder 417 between the enlargement 411 and the lower portion 412 in which a portion of the loop 422 opposite the trigger 421 is further pushed to dispose in the aperture 27 (i.e., locked) by the expanding spring 43. As a result, the actuation member 42, the spring 43, and the extension 26 are held captive. This is the closed state of the umbrella (see FIGS. 7 and 7A). The rib fixing assembly 5 comprises an upper cup 51 having a bottom opening with the inner lower tube 311 snugly inserted therethrough and further into the handle 21 to fasten therein by molding, and a spring 55 compressed between the handle 21 and an underside of the cup 51 to fasten the cup 51 at one of the flanges 416.

Referring to FIGS. 8 and 8A, for opening the umbrella a user may simply push the trigger 421 to move the loop 42 inward to clear the aperture 27. Thus, the extension 26 (i.e., the sleeve 22) is free to slide upward to pass the coupling 32 without being interfered. At the same time, the spring 43 is compressed. A releasing of the trigger 421 will thus expand the spring 43 to move the actuation member 42 back to its inoperative position.

Referring to FIG. 9, after the umbrella has been opened, for example, a turning of the lock device 33 may engage the lower tube 311 with the upper tube 312 together. To the contrary, a further turning of the lock device 33 may disengage the lower tube 311 with the upper tube 312. In brief, turning the lock device 33 may effect a desired section-less length or section-more length adjustment of the shank 31. As shown in FIG. 9, for example, a lower portion of the upper tube 312 may slide into the lower tube 311 for adjustment of decreasing desired length of the shank assembly 3.

Referring to FIGS. 10 to 13, rib tips 231 are adapted to dispose proximate the lower portion 412 after closing the umbrella. Next, a user may manually put the rib tips 231 into the cup 51 for fastening. This can hold ribs 23 in place and reduce size of the closed umbrella to a minimum. A user may further tie a tie closure to tie canopy 24 (see FIG. 13). For opening the umbrella, a user may simply press the cup 51 toward the handle 21 to compress the spring 52 until the rib tips 231 clear the cup 51. Next, a releasing of the pressing will expand the spring 52 upward to slide the cup 51 back to its inoperative position.

Referring to FIGS. 14 and 15, a user may quickly decrease a length of the shank 31 (i.e., length of the upper tube 312) by turning (i.e., unfastening) the lock device 33 (see FIGS. 5 and 5A) and then turn (i.e., fasten) the lock device 33 again to fasten the shank 31 at this adjusted length in response to strong wind (see FIGS. 6 and 6A). It is seen that a distance H2 between a virtual wind exertion plane on the canopy 24 and the handle 21 of the umbrella 2 of the invention (see FIG. 15) is relatively smaller than a distance H1 between a virtual wind exertion plane on the canopy and the handle 15 of the umbrella 1 of the prior art (see FIG. 14). This means that pressure exerted upon the umbrella by strong wind is reduced significantly by the umbrella of the invention since a user may easily adjust length of the shank.

While the invention herein disclosed has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of the invention set forth in the claims. 

1. A lock mechanism mounted in a large umbrella having a handle, a plurality of ribs, a plurality of spreaders, and a canopy, the lock mechanism comprising: a sliding sleeve connected to the spreaders and including a lower extension and an aperture on a surface of the extension; a shank assembly including a telescopic shank and a lock device disposed in the shank; an actuation assembly including a hollow upper enlargement with the extension received therein, a transverse first opening formed on the enlargement, and a spring biased actuation member adapted to have a first predetermined portion disposed in the aperture for locking the extension in a closed position of the umbrella, and a second predetermined portion disposed externally of the enlargement; and a spring biased rib fixing assembly disposed between the handle and the actuation assembly, the rib fixing assembly being adapted to fix tips of the ribs in the closed position of the umbrella; whereby pushing the second predetermined portion of the actuation assembly will disengage the first predetermined portion with the aperture to unlock the extension of the sliding sleeve for sliding the sliding sleeve upward to open the umbrella, and turning the lock device of the shank assembly will effect a subsequent section-less length or section-more length adjustment of the shank.
 2. The lock mechanism of claim 1, wherein the shank comprises a fixed lower tube, a sliding upper tube adapted to partially slide into the lower tube, a coupling disposed on an upper end of the lower tube, and a lock device secured to a lower end of the upper tube.
 3. The lock mechanism of claim 2, wherein the lock device comprises a barbell member secured to the lower end of the upper tube and including an eccentric groove formed on an intermediate portion, an eccentric bar formed adjacent the groove, and a projecting stop formed on a surface of the bar; and a flexible, eccentric C-shaped fastening member fitted on the groove.
 4. The lock mechanism of claim 3, wherein the fastening member comprises an eccentric arcuate first member, an eccentric arcuate second member thinner than the first member, and a flexible portion interconnected the first and the second members, and a protuberance formed on a top of the second member.
 5. The lock mechanism of claim 2, wherein the coupling comprises a top narrow section having an inner diameter smaller than that of the lower tube for preventing the lower tube from disengaging with the upper tube.
 6. The lock mechanism of claim 1, wherein the extension comprises two opposite projecting members formed above the aperture, and wherein the enlargement further comprises two notches on its inner surface engaged with the projecting members of the extension.
 7. The lock mechanism of claim 2, wherein the coupling has an outer diameter smaller than an inner diameter of the sleeve such that the sleeve is adapted to pass through the coupling by sliding in opening or closing the umbrella.
 8. The lock mechanism of claim 1, wherein the enlargement further comprises a receptacle opposite the first opening for anchoring the actuation member, and a lower projecting portion including a plurality of flanges formed therearound; wherein the second predetermined portion of the actuation member is formed as a trigger; and wherein the actuation member further comprises a loop interconnected the first and the second predetermined portions, a cavity formed in the first predetermined portion opposite the receptacle, and a first elastic member having one end anchored in the receptacle and the other end anchored in the cavity.
 9. The lock mechanism of claim 8, wherein the rib fixing assembly comprises a cup including a bottom second opening urged against one of the flanges, and a second elastic member compressed between the cup and the handle.
 10. The lock mechanism of claim 9, wherein the tips of the ribs are adapted to dispose proximate the cup in response to closing the umbrella. 